my first scan..issues with o2s

[Jimcz]

test 1 street tune.hpl hi, this is my file from my 04 z06 headers and vararam...so a street tune was done, im new with hptuners.. my o2 sensors go lazy at idle I feel power come and go.. not sure if I did this right? thanks jim

[Jimcz]

Anyone?

[MarcusMilner]

Jim, you should also post your tune, that gives everyone the big picture. O2's will be slow responding with headers. 1st thing to do is your ve and maf tables, worry about idle after you work on the airflow tables. Do a search on how to set up your scanner-what channels to use and how to set up charts and graphs. Some settings will need to be changed in the tune also. You will need a wideband for wide open throttle tuning also, stock narrowband O2's are not accurate at wot, they will just show 0.0. and to answer your last question-nope.

[Jimcz]

I have the file listed above..is it not working?

[TCSS07]

No, you posted the log file. Hes asking for you to post the tune file

[Jimcz]

Oh ok..i will do that.vette doctors street tune.hpt

[Jimcz]

file is posted..thanks jim

[AutoTune]

I installed OBX stainless headers on my Gen 3 5.3L. After a bunch of tinkering I finally found out that headers cool the exhaust faster than stock manifolds, therefore the o2 sensors are getting too cool at idle. The master techs I work with recommended fiberglass header wrap to contain the heat and get it all the way to the o2 sensors.

I kept having o2 errors still but once I disabled the DTCs [Engine Diagnostics > DTC Tab > O2 DTCs p0131 etc and p1140 or something insufficient o2 switching further down] for o2-related stuff they stopped kicking themselves into a failure loop. After they are disabled use the scanner to force a 14.7 AFR in the special functions tab and see how it runs with that ON.

Still tinkering to fix closed loop.. it works great until higher RPM it gets really lean. I forced it into Open Loop only for a while by putting the Closed Loop Enable vs. ECT to 284 all the way down and disabling STFT and LTFT. [Engine > Fuel > Open/Closed Loop] This fixed my lean at high RPM issue but it doesn't run as smooth as Closed Loop would.. however my exhaust barely has any stink to it so it's right in the sweet spot where it gets just enough fuel but not too much.

Good luck.. I started in February of this year so I am definitely not an expert but I think you mainly just need header wrap to keep those o2 nice and hot (if you're lucky). Mine are heated but I think the little heating element wasn't enough during winter.

EDIT: My truck is an 01 so some HP Tuners stuff might be different but like I said I would try header wrap first or ask others if they think the header wrap would help keep those o2s hot enough to stay in their operating temp range before changing PCM variables.

[Jimcz]

Funny thing i have no codes or check engine light. It had been acting this way when i t was just headers cai and STOCK tune. I feel like also something is going on with either my throttle body,drive by wire.. it feels like the throttle body doesnt open all the way..

[AutoTune]

First thing I would do is add a few channels in your scanner. Make sure you are logging Knock Retard because I bet you're getting some pings where it runs lean. Go to the "Channels" box on left and click the gear with a green + on it (Add Channel) and add Knock Retard, Injector Pulsewidth Bank 1 & 2 also. Just glancing at the fuel trim averages, they look good, however on the graph I noticed some +10% - +15% spots on STFT.

Make sure you set up VCM scanner with all the right channels being logged. Don't log too many, only the ones you need, but it definitely helps anyone else trying to assist you. I like making other tables too like O2 mV vs. AFR Commanded to help me understand the tune better.

Looking at the o2 table, the 900s are rich, probably caused by PE (power enrichment) when you stomp the pedal down and hit those higher RPM. The lower RPM ones are lower, maybe some lean spots in there causing the hesitation. Especially the low kPa spots, that would cause the throttle body blade sticking feeling. I am more familiar with a 5.3 than a 5.7 though..

[Jimcz]

so by looking at the tune is it safe to drive? if this was really street tuned then this should not be like this correct? this is the whole idea when getting a street tune...

[AutoTune]

I've noticed that unless you disable a lot of fail-safes like Knock Sensors, COT then it may be risky but yours looks like it should drive alright.

I also disabled TCS Method in bottom left of Torque Management. This retards spark when the tires slip which is horrible for people who drive like me. The spark advance seems a little higher but vettes do have a more aggressive cam / intake / airflow usually so maybe that's where it started. If not, log KR in scanner, if you see knock try a higher octane fuel.

I bought Greg Banish's book on Amazon for like $15 and would highly recommend. I'd send you mine but I still need to re-read it. It's a great starter guide and there's other more in depth books available on there as well. I would definitely recommend Banish's book first though.

Don't forget to Add Channels: Knock Retard (generic if prompted) and Inj Pulsewidth B1 & B2. Also might want to set up some tables showing AFR Commanded [Middle] vs. MAP kPa [Side] vs. RPM [Top] and log another drive with the extra channels. Careful, if you have a recording and change the channels it WILL erase the open file.

Also try turning your MAF, mine wasn't in the main airflow which was towards the back of CAI tube not bottom / middle where I originally put it. The MAF does most of the work in calculating engine fueling.

Post your new logs with KR on and Inj PW B1 & B2 so we can go from there. AFR tables would rock too. If you need help setting those up PM me and I will walk you through it. Happy Sunday!


https://www.amazon.com/Engine-Manage...40_&dpSrc=srch

I got a "used" one that looked brand new

[Jimcz]

Wow, thanks for that info..i actually think i found my problem..throttle mapping it feels like im pushing my gas pedal and the throttle body is not opening as fast..this must explain why i have no codes or check engine light. Like i said this has been happing before any tune was put in.i was reading alot about this and people with this problem. I had this problem with my 04 svt cobra i pushed the gas pedal down and the car didn't go anywhere fast..turns out my gas pedal was alittle bent and stopping and hitting the carpet..same feeling with this car..im just going to have the header cai tune that i originally had from ecs i will install that then start there..im sorry i bought the new hptuners no w/b...and theres no updates yet. Thanks jim

[AutoTune]

Mine was sticking from carbon on the back of the TB blade. When I was working on the knock sensors, intake gaskets etc I cleaned it really well from the backside and cleaned the intake out from EGR soot.. so I know the feeling!

Glad you fixed your problem, don't forget to add those channels though! Experiment with other channels and tables too, those help me understand the PCM better. That $15 book is well worth it too. WB is definitely nice, however at lower throttle you can still tune with HPT and stock narrowband. Yes it is not favorable, however it is a start. I can hear when my engine is making it's "lean noise" and it feels sluggish so I try to enrich those RPM/ kPa zones. Usually I confirm them on the STFT table. Don't forget to check out the o2 table and see if you can enrich those lean zones I mentioned!

Also curious, does yours have a physical cable or electronic pedal to actuator or whatever newer design?